Plastic Bottles for Sorting Floating Microplastics in Sediment
Round 1
Reviewer 1 Report
In my opinion the introduction must be revised in the writing mode.
Some sentences, even if relevant, do not follow a correct logic (i.e., lines 42-43).
For each figure it must be specified which are the MPs (red) and the sand (yellow).
Some milestones should be entered referring to all the methods mentioned (i.e., spoon method, overflow method, etc.) .
Some "problems" mentioned in paragraph 4.3 need to be investigated. In particular, the method should be tested with sand to verify the effects (line 517).
As indicated in line 525, the bottle material could increase the MPs content; have you thought of a different material?
In my view, the laboratory conditions reproduced may not correspond to the real conditions found in field activities. Therefore, the work must also be tested on marine sediments where the composition of the sand and the state of degradation of the plastics could vary the results obtained under ideal conditions.
It should also be assessed if there are any variations that can occur in different environments (e.g. sea water, transitional waters, etc.).
Author Response
Please see an attached file.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript describes the study about " Plastic bottles for sorting floating microplastics in sediment" this manuscript has enough scientific content to be published, and the studies are well carried out. Anyhow, there are some concerns in the manuscripts as follow:
1. The knowledge gap should be clearly mentioned in the Introduction to understand this work's novelty better. Please put your objective and hypothesis statement at the end of the Introduction section.
2. The section of "Results and discussion" is not well-presented. There is an insufficient scientific discussion of the obtained results and documentation with the literature, and this section requires additional support to strengthen the argument. Furthermore, the manuscript requires some proofreading.
3. English needs to be carefully checked and edited by a native English speaker.
4. As the authors did not discuss any significant limitations of the current work, it may be worthwhile to mention a few.
5. The authors are advised to compare their results with already published results. The advantages of the proposed method compared with other methods have to be clearly described.
6. The figures and tables are clearly marked but, in some cases, not well discussed. The conducted statistical model needs to develop and discuss deeper
7. Although this appears to be a novel way for sorting microplastic using bottles, the authors did not discuss the practical/technical aspects of implementing the strategy in figures 7b and 8. There is a substantial likelihood of leakage.
8. The use of PET bottles can potentially attract and adhere to some microplastics because of their electrostatic force, particularly for the medium and small-sized microplastic. Moreover, the authors only use large microplastic (>1000 μm/1 mm). Please be crystal clear in this.
9. How do you control the potential loss of microplastics due to the PET bottle?
10. Could you please provide the data regarding this method's accuracy and anti-interference performance.
9. More details must be added in the conclusion section. The conclusion of the work needs to be more convincing and sufficiently supported by experimental evidence.
Author Response
Please see an attached file.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors put a lot of effort to improve the manuscript. The author has sufficiently considered all the points made in the previous manuscript. From my perspective, the manuscript deserves publication
